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Comparison of preschool vision screening methods in a population with a high prevalence of astigmatism
J M Miller1, V Dobson, E M Harvey
1Department of Ophthalmology, University of Arizona, Tucson 85711, USA. jmiller@eyes.arizona.edu
Insights
Objective automated screening methods like Retinomax K-Plus Noncycloplegic Autorefraction Screening (NCARS) and Nidek KM-500 Keratometry Screening (KERS) are superior for detecting childhood astigmatism needing glasses. These tools outperformed visual acuity and photoscreening methods in a study of Native American children.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Public Health Screening
Background:
- Astigmatism is a common refractive error in children, potentially impacting visual development.
- Early detection and correction of astigmatism are crucial for optimal visual outcomes in young children.
- Native American populations exhibit a high prevalence of astigmatism, often corneal in origin.
Purpose of the Study:
- To evaluate and compare the efficacy of four distinct screening methods for identifying astigmatism in preschool-aged children.
- To determine which screening techniques are most effective in detecting astigmatism requiring spectacle correction in 3- to 5-year-olds.
Main Methods:
- Four screening methods were assessed: Lea Symbols Visual Acuity Screening (LSVAS), MTI Photoscreening (MTIPS), Nidek KM-500 Keratometry Screening (KERS), and Retinomax K-Plus Noncycloplegic Autorefraction Screening (NCARS).
- The study involved 379 preschool children from a Native American tribe with high astigmatism prevalence.
- Cycloplegic refraction was used as the gold standard to confirm the need for spectacle correction.
Main Results:
- Automated methods, Retinomax K-Plus Noncycloplegic Autorefraction Screening (NCARS) and Nidek KM-500 Keratometry Screening (KERS), demonstrated superior performance with higher areas under the Receiver Operating Characteristic (ROC) curve (0.98 and 0.92, respectively).
- Testability rates were significantly higher for NCARS (99.5%) and KERS (99.7%) compared to MTIPS (93.5%) and LSVAS (92.0%).
- Astigmatism requiring spectacle correction was identified in 33% of the study participants.
Conclusions:
- Objective, automated screening methods (NCARS and KERS) are more effective than subjective visual acuity screening and photoscreening for identifying children needing astigmatism correction.
- The findings support the use of automated autorefraction and keratometry for efficient and accurate preschool astigmatism screening.
- These advanced screening tools offer improved detection rates and testability in pediatric populations, particularly those at high risk for astigmatism.
Purpose:
To compare the effectiveness of four methods of screening 3- to 5-year-old children for astigmatism high enough to require spectacle correction.
Methods:
Lea Symbols Visual Acuity Screening (LSVAS), MTI Photoscreening (MTIPS), Nidek KM-500 Keratometry Screening (KERS), and Retinomax K-Plus Noncycloplegic Autorefraction Screening (NCARS) were attempted on 379 preschool children who are members of a Native American tribe having a high prevalence of astigmatism that is primarily corneal in origin. The need for spectacle correction was determined by cycloplegic refraction. Receiver Operating Characteristic (ROC) curves were fit, confidence intervals were determined, and area under the curves was compared.
Results:
Astigmatism > or = 1.00 D was present in the right eye of 47.5% and in the left eye of 48.0% of children. Spectacles were prescribed for children < 48 months of age who had cylinder > or = 2.00 D and children > or = 48 months who had cylinder > or = 1.50 D, with the result that 33% of subjects required spectacles. Area under the ROC curve was 0.98 for NCARS, 0.92 for KERS, 0.78 for MTIPS, and 0.70 for LSVAS, and each of these values differed significantly from the other three (all P < 0.007). Testability was significantly higher for NCARS (99.5%) and KERS (99.7%) than for MTIPS (93.5%) and LSVAS (92.0%).
Conclusions:
In a population that included many children with astigmatism, objective, fully automated screening methods (NCARS and KERS) were superior to both visual acuity screening and photoscreening with subjective interpretation in identifying children who had astigmatism requiring spectacle correction.
